The present invention relates to new water-soluble trisazo compounds and colored articles therefrom.
Among various color recording methods, one typical method is the recording method by means of ink jet printers wherein ink droplets are produced and deposit on various materials to be recorded such as papers, films and fabrics so that recordings are effected. This method has advantages that it is silent since materials to be recorded are not contacted with a recording head and that miniaturization, speeding up and color printing can be easily achieved. Thus, it has recently come into wide use and it is expected to greatly spread in future.
As inks for pens, felt-tip pens and the like as well as inks for ink jet printers, aqueous inks comprising water-soluble dyes dissolved in aqueous media are used. Generally, the aqueous inks comprise water-soluble organic solvents in order to prevent the inks from clogging in nibs and ink delivery nozzles. These inks should meet the requirements that they can form images having a high optical density, that they do not clog nibs and ink delivery nozzles, that they are easily dried on materials to be recorded, that they hardly blot and that they have excellent storage stability. In addition, images therefrom should have sufficient light and water resistances.
Various inks having different hues are prepared from various dyes. Among the inks, black inks are important since they are used in mono-color and full-color images. As dyes for black inks, many dyes have been proposed as described in prior patent applications, for example, JP-55144067A(1980), JP-57207660A(1982), JP-58147470(1983), JP-59093766A(1984), JP-62190269A(1987), JP-62246975A(1987), JP-63022867A(1988), JP-63033484A(1988), JP-01093389A(1989), JP-02140270A(1990), JP-03167270A(1991), JP-03200852A(1991), JP-04359065A(1992), JP-06172668A(1994), JP-06248212A(1994), JP-07026160A(1995), JP-07268256A(1995) and the like. However, the prior dyes cannot satisfy the commercial requirements as described above.
An object of the present invention is to provide a black recording fluid having a high solubility, stable even after a long storage, capable of forming a printed image with a high optical density and excellent in water and light resistances.
The present inventors have earnestly investigated in order to solve the aforementioned problem, achieving the present invention.
Accordingly, the present invention relates to:
(1) a trisazo compound represented by the following general formula (1): 
wherein
D is an 8-hydroxy-1-naphthyl group substituted with one or two sulfo groups;
A is a group of the general formula (2) or (3): 
wherein R1 and R2 are each independently hydrogen, amino, hydroxyl, carboxyl, sulfo, phosphono, (C1-C4)alkoxycarbonyl, (C1-C4)alkyl optionally substituted with hydroxy or (C1-C4)alkoxy, (C1-C4)alkoxy optionally substituted with hydroxy or (C1-C4)alkoxy, (C2-C4)alkanoylamino optionally substituted with hydroxy or (C1-C4)alkoxy or ureido, R3 is hydrogen, (C1-C4)alkyl or (C1-C4)alkoxy, and R4 is hydrogen, sulfo or phosphono;
B is a group represented by the general formula (4): 
wherein R5, R6 and R7 are each independently hydrogen, hydroxyl, amino, carboxyl, (C1-C4)alkoxy, (C1-C4)alkoxycarbonyl, (C1-C4)alkyl, mono- or bis-carboxy-(C1-C3)alkylamino, carboxy-(C1-C3)alkoxy, (C1-C4)alkylamino optionally substituted with hydroxy or (C1-C4)alkoxy, (C1-C4)alkanoylamino, sulfo, halogen or ureido; and
m is 0 or 1,
or its salt;
(2) a salt of a trisazo compound as defined in (1) wherein the salt is a lithium salt, a sodium salt, or an ammonium salt represented by the general formula (5): 
wherein R8 to R11 are each independently hydrogen, (C1-C4)alkyl, hydroxy-(C1-C4)alkyl or hydroxyethoxy-(C1-C4)alkyl group;
(3) a trisazo compound or its salt as defined in (1) or (2) wherein D is
8-hydroxy-3,6-disulfo-1-naphthyl,
8-hydroxy-4,6-disulfo-1-naphthyl,
8-hydroxy-2,4-disulfo-1-naphthyl,
8-hydroxy-3,5-disulfo-1-naphthyl,
8-hydroxy-4,7-disulfo-1-naphthyl,
8-hydroxy-5,7-disulfo-1-naphthyl,
8-hydroxy-4-sulfo-1-naphthyl,
8-hydroxy-5-sulfo-1-naphthyl, or
8-hydroxy-6-sulfo-1-naphthyl;
(4) a trisazo compound or its salt as defined in any one of (1) to (3) wherein A is the group of the general formula (2) wherein R1 and R2 are each independently hydrogen, methyl, ethyl, methoxy, ethoxy, methoxyethoxy, amino, hydroxyl, carboxyl, sulfo, acetylamino, n-propionylamino or ureido, or the general formula (3) wherein R3 is hydrogen, methyl or methoxy and R4 is hydrogen or sulfo;
(5) a trisazo compound or its salt as defined in any one of (1) to (4) wherein A is the group of the general formula (2) wherein R1 is methyl, methoxy or methoxyethoxy and R2 is hydrogen, methyl, methoxy, amino, hydroxyl, acetylamino or ureido;
(6) a trisazo compound or its salt as defined in any one of (1) to (4) wherein A is the group of the general formula (3) wherein R3 is hydrogen or methoxy and R4 is hydrogen or sulfo;
(7) a trisazo compound or its salt as defined in any one of (1) to (6) wherein B is the group of the general formula (4) wherein R5 is hydrogen, methyl, methoxy, chlorine, carboxyl or sulfo, and R6 and R7 are each independently hydroxyl, amino, carboxymethylamino, carboxymethoxy, acetylamino or ureido;
(8) a trisazo compound or its salt as defined in any one of (1) to (7) wherein m is zero;
(9) an aqueous ink composition containing a trisazo compound or its salt as defined in any one of (1) to (8);
(10) an article colored with a trisazo compound as defined in any one of (1) to (8) or an aqueous ink composition as defined in (9); and
(11) a colored article as defined in (10) wherein coloring is effected by means of a printer.
The present invention will be fully explained below.
In the compound represented by the aforementioned formula (1), D is an 8-hydroxy-1-naphthyl group substituted with one or two sulfo groups. Preferably, it includes 8-hydroxy-3,6-disulfo-1-naphthyl, 8-hydroxy-4,6-disulfo-1-naphthyl, 8-hydroxy-2,4-disulfo-1-naphthyl, 8-hydroxy-3,5-disulfo-1-naphthyl, 8-hydroxy-4,7-disulfo-1-naphthyl, 8-hydroxy-5,7-disulfo-1-naphthyl, 8-hydroxy-4-sulfo-1-naphthyl, 8-hydroxy-5-sulfo-1-naphthyl, 8-hydroxy-6-sulfo-1-naphthyl and the like. 8-Hydroxy-3,6-disulfo-1-naphthyl, 8-hydroxy-4,6-disulfo-1-naphthyl, 8-hydroxy-2,4-disulfo-1-naphthyl, 8-hydroxy-4-sulfo-1-naphthyl or the like is more preferable.
In A and B in the aforementioned formula (1), examples of (C1-C4)alkyl include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl or the like, preferably methyl or ethyl. Examples of (C1-C4) alkyl group substituted with hydroxy or (C1-C4)alkoxy include 2-hydroxyethyl, 2-hydroxypropyl, 1-hydroxy-1-methylethyl, methoxyethyl, ethoxyethyl or the like, preferably 2-hydroxyethyl or methoxyethyl. Examples of (C1-C4)alkoxy group optionally substituted with hydroxy or (C1-C4)alkoxy include methoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy, sec-butoxy, tert-butoxy, 2-hydroxyethoxy, 2- or 3-hydroxypropoxy, methoxyethoxy, ethoxyethoxy, n-propoxyethoxy, isopropoxyethoxy, n-butoxyethoxy, methoxypropoxy, ethoxypropoxy, n-propoxypropoxy, isopropoxybutoxy, n-propoxybutoxy, 2-hydroxyethoxyethoxy or the like, preferably methoxy, ethoxy, methoxyethoxy or ethoxyethoxy. Methoxy or methoxyethoxy is particularly preferable. Examples of (C1-C4)alkylamino group optionally substituted with hydroxy or (C1-C4)alkoxy include 2-hydroxyethylamino, 2-hydroxyethylmethylamino, N,N-di(2-hydroxyethyl)amino, 2-hydroxypropylamino, 3-hydroxypropylamino, methoxyethylamino, ethoxyethylamino or the like, preferably 2-hydroxyethylamino, methoxyethylamino or 3-hydroxypropylamino. (C1-C4)alkanoylamino group optionally substituted with hydroxy or (C1-C4)alkoxy include acetylamino, n-propionylamino, isopropionylamino, hydroxyacetylamino, 2- or 3-hydroxy-n-propionylamino, 2- or 3-methoxy-n-propionylamino, butyrylamino or the like, among which acetylamino is particularly preferable. Examples of mono- or bis-carboxy-(C1-C3)alkylamino group include carboxymethylamino, carboxyethylamino, carboxypropylamino, bis-carboxymethylamino, bis-carboxyethylamino, bis-carboxypropylamino, preferably carboxymethylamino, bis-carboxymethylamino or carboxyethylamino. Examples of carboxy-(C1-C3)alkoxy include carboxymethoxy, carboxyethoxy and carboxypropoxy, particularly preferably carboxymethoxy.
Preferably, R1 and R2 are each independently hydrogen, methyl, ethyl, methoxy, ethoxy, methoxyethoxy, ethoxyethoxy, amino, hydroxyl, carboxyl, sulfo, phosphono, acetylamino, n-propionylamino and ureido. Hydrogen, methyl, methoxy, methoxyethoxy, amino, hydroxyl, carboxyl, acetylamino or ureido is particularly preferable.
The general formula (2) is preferably derived from each of the following intermediates: 1-Amino-2-methoxy-5-methylbenzene, 1-amino-2,5-dimethylbenzene, 1-amino-2-methoxy-5-acetylaminobenzene, 1-amino-2-methoxyethoxy-5-acetylaminobenzene, 1-amino-2-methoxybenzene, 1-amino-2-methylbenzene, 1-amino-2,5-dimethoxybenzene, 1-amino-2-methyl-5-acetylaminobenzene, 1-amino-2-methoxy-5-ureidobenzene, 1-amino-2-methyl-5-ureidobenzene, 1-amino-3-methoxybenzene, 1-amino-3-methylbenzene, 1-amino-2-(2xe2x80x2-hydroxyethoxy)-5-methylbenzene, 3-aminobenzoic acid, 3-amino-4-methylbenzoic acid, 3-amino-4-methoxybenzoic acid, 2,4-diaminobenzoic acid, 2,4-diaminobenzenesulfonic acid, 2-amino-4-acetylaminobenzenesulfonic acid, 3-aminobenzenephosphonic acid, 4-methoxy-3-aminophenol and 2,4-diaminoanisole.
R3 is preferably hydrogen, methyl, ethyl, methoxy or ethoxy. Particularly, hydrogen, methyl or methoxy is preferable.
R4 is preferably sulfo.
It is particularly preferable that the residue A of the general formula (3) is derived from the intermediate 1-aminonaphthalene-2-sulfonic acid, 1-aminonaphthalene-3-sulfonic acid, 1-aminonaphthalene-5-sulfonic acid, 1-aminonaphthalene-6-sulfonic acid, 1-aminonaphthalene-7-sulfonic acid, 1-aminonaphthalene-8-sulfonic acid or 1-amino-2-methoxynaphthalene-6-sulfonic acid.
A component from which the naphthalene residue in the general formula (1) is derived is 1-hydroxy-3-sulfo-7-aminonaphthalene (xcex3 acid) when m is 0 and 1-hydroxy-3,6-disulfo-7-aminonaphthalene (2R acid) when m is 1.
R5 is hydrogen, methyl, methoxy, chlorine, carboxyl, sulfo or the like. Methyl, ethyl, methoxy, ethoxy or sulfo is preferable. Particularly, hydrogen or sulfo is preferable.
R6 and R7 are each independently hydroxyl, amino, carboxymethylamino, carboxypropylamino, bis-carboxymethylamino, acetylamino, ureido or the like. Hydroxyl, amino, acetylamino or carboxymethylamino are particularly preferable.
Examples of intermediate from which the residue B of the general formula (4) is derived include 1,3-phenylenediamine, resorcin, 3-aminophenol, 2-amino-4-acetylaminobenzesulfonic acid, 2,4-diaminobenzenesulfonic acid, 2,4-diaminobenzoic acid, 2,4-diaminotoluene, 2,4-diaminoanisole, 2,4-diaminochlorobenzene, 1,3-bis-carboxymethylaminobenzene, 1-amino-3-acetylaminobenzene, 1-amino-2-methoxy-5-acetylaminobenzene, 1-amino-2-methyl-5-acetylaminobenzene, 1-amino-2-methoxy-5-ureidobenzene, 2,4-dihydroxybenzoic acid, 1-amino-2-methyl-5-ureidobenzene or the like. 1,3-Phenylenediamine, resorcin, 3-aminophenol or 2,4-diaminobenzenesulfonic acid is preferable. Their mixture may be used.
Salts are those of inorganic or organic cations. Suitable inorganic salts are alkali metal or alkaline earth metal salts. Preferable inorganic salt are lithium or sodium salt. And, suitable organic salts are ammonium salts represented by the general formula (5). 
In the above general formula (5), R8 to R11 are each independently hydrogen, (C1-C4)alkyl, hydroxy-(C1-C4)alkyl or hydroxyethoxy-(C1-C4)alkyl. Examples of (C1-C4) alkyl include methyl, ethyl, n-propyl, i-propyl, n-butyl, i-butyl, sec-butyl, tert-butyl or the like, Examples of hydroxy-(C1-C4)alkyl include hydroxymethyl, hydroxyethyl, 3-hydroxypropyl, 2-hydroxypropyl, 4-hydroxybutyl, 3-hydroxybutyl, 2-hydroxybutyl or the like. Examples of hydroxyethoxy-(C1-C4)alkyl include hydroxyethoxymethyl, 2-hydroxyethoxyethyl, 3-hydroxyethoxypropyl, 2-hydroxyethyoxypropyl, 4-hydroxyethoxybutyl, 3-hydroxyethoxybutyl, 2-hydroxyethoxybutyl or the like.
Examples of the compound of the general formula (5) are shown in Table 1.
Examples of the trisazo compound represented by the general formula (1) are illustrated in the general formula (1-1) (Table 2) to the general formula (1-5) (Table 27).
The compound represented by the general formula (1) can be synthesized, for example, according to the following method. That is, the compound of the general formula (1) can be synthesized by:
diazotizing a compound of the general formula (6): 
wherein Y is hydrogen, halogen or (C1-C4) alkyl and A is as defined above, in an aqueous medium;
coupling with a compound of the general formula (7): 
wherein m is 0 or 1;
hydrolyzing the resultant disazo compound of the general formula (8): 
wherein A, Y and m are as defined above, to a compound of the general formula (9): 
wherein A and m are as defined above;
diazotizing the compound of the general formula (9); and
coupling with a compound of the general formula (4xe2x80x2): 
wherein R5, R6 and R7 are as defined above. Alternatively, the compound of the general formula (8) may be diazotized again, coupled with the compound of the general formula (4xe2x80x2) and then hydrolyzed to obtain the compound of the general formula (1).
Each of the compounds of the general formulae (6), (7) and (4xe2x80x2) can be prepared according to the known method per se.
Diazotization of the compound of the general formula (6) is effected according to the known method per se, for example, using nitrites such as an alkali metal nitrite (e.g. sodium nitrite) at xe2x88x925 to 30xc2x0 C., preferably 0 to 10xc2x0 C. in an aqueous inorganic acid medium.
Coupling of the diazo compound of the general formula (6) with the compound of the general formula (7) is effected under the known condition per se. It is conveniently effected in an aqueous or aqueous organic medium at xe2x88x925 to 30xc2x0 C., preferably 0 to 10xc2x0 C. under the weak acidic or alkaline pH. Preferably, it is effected under the neutral or alkaline pH, e.g. 7 to 11. The pH is adjusted by the addition of any base. The base to be used includes alkali metal hydroxides such as lithium hydroxide and sodium hydroxide; alkali metal carbonates such as lithium carbonate, sodium carbonate and potassium carbonate; alkali metal acetates such as sodium acetate; ammonia; or organic amines. The compounds of the general formulae (6) and (7) are used in approximately stoichiometric amounts in this reaction.
The preparation of the compound of the general formula (9) by hydrolyzing the compound of the general formula (8) is effected according to the known method per se. The heating in an aqueous alkaline medium is convenient. For example, it is effected by adding sodium or potassium hydroxide to a reaction solution containing the compound of the general formula (8) until the pH is 11 or more and then heating to the temperature of 20 to 150xc2x0 C., preferably 30 to 100xc2x0 C. Preferably, the pH of the reaction solution is kept to be 10 to 12.
Diazotization of the compound of the general formula (9) resulting from hydrolyzing is effected under the same condition as that described in the diazotization of the compound of the general formula (6).
Coupling of the diazotized product of the compound of the general formula (9) with the compound of the general formula (4xe2x80x2) is effected under the known condition per se. It is effected in an aqueous or aqueous organic medium at the temperature of 0 to 30xc2x0 C., preferably 10 to 20xc2x0 C. and the pH of 4 to 10, preferably 6 to 8.
After the coupling reaction, the compound represented by the general formula (1) of the present invention can be isolated in the form of free acid by adding any mineral acid. The thus-isolated free acid may be washed with water or an acidified water to remove inorganic salts. The acid type dye having a low salt content can be converted to a solution containing its corresponding salt by neutralizing with hydroxide and/or carbonate (e.g. LiOH, Li2CO3, NaOH, Na2CO3 or K2CO3) or amine in an aqueous medium. Preferable examples of the amine include ammonia, ethanolamine, diethanolamine, triethanolamine, N-methyl-N-ethanolamine, N-methyl-N,N-diethanolamine, 2-(2-hydroxyethoxy)-ethylamine, di-2-(2-hydroxyethoxy)-ethylamine, tri-2-(2-hydroxyethoxy)-ethylamine or the like.
The trisazo compound represented by the general formula (1) is suitable for dyeing papers, natural fibers such as celluloses, wools and leathers and blended yarn fabrics of natural and synthetic fibers. Further, it is suitable for the preparation of writing inks and recording liquid.
The reaction liquid containing the trisazo compound represented by the general formula (1) of the present invention can be used as it is in the preparation of recording ink compositions. Alternatively, the above compound is dried, for example, spray-dried and then processed into an ink composition.
As a finished product, the recording ink composition contains the trisazo compound represented by the general formula (1) of the present invention in an amount of, for example, about 0.1 to 20% by weight, preferably about 1 to 10% by weight, more preferably about 2 to 8% by weight.
The ink composition of the present invention may comprises a water-soluble organic solvent in an amount of, for example, 0 to 30% by weight and an ink formulating agent in an amount of, for example, 0 to 5% by weight.
The aqueous ink composition of the present invention comprises the trisazo compound represented by the general formula (1) dissolved in water or an aqueous solvent (water containing any water-soluble organic solvent or any water-compatible organic solvent). When this aqueous ink composition is used as an ink for ink jet printers, the trisazo compounds having less amounts (for example, about 1% by weight or less) of inorganic substances such as chlorides and sulfates of metallic cations are preferably used. Such trisazo compounds having less amounts of the inorganic substances may be prepared by subjecting to the desalting treatment according to any conventional method such as the method using a reverse osmotic membrane.
Examples of water-soluble organic solvents include (C1-C4)alkanol such as methanol, ethanol, propanol, isopropanol, butanol, isobutanol, sec-butanol and tert-butanol; carboxamides such as N,N-dimethylformamide and N,N-dimethylacetamide; lactams such as xcex5-caprolactam and N-methylpyrrolidin-2-one; cyclic ureas such as 1,3-dimethylimidazolin-2-one and 1,3-dimethylhexahydropyrimid-2-one; ketones and ketoalcohols such as acetone, methyl ethyl ketone and 2-methyl-2-hydroxypentan-4-one; cyclic ethers such as tetrahydrofuran and dioxane; mono-, oligo- or poly-alkylene glycols or thioglycols having (C2-C6)alkylene units such as ethylene glycol, 1,2- or 1,3-propylene glycol, 1,2- or 1,4-butylene glycol, 1,6-hexylene glycol, diethylene glycol, triethylene glycol, dipropylene glycol, thiodiglycol, polyethylene glycol and polypropylene glycol; polyol (triol) such as glycerol and hexane-1,2,6-triol; (C1-C4)alkyl ethers of polyhydric alcohols such as ethylene glycol monomethyl ether or monoethyl ether, diethylene glycol monomethyl ether or monoethyl ether and triethylene glycol monomethyl ether or monoethyl ether; xcex3-butyrolactone; disulfoxide and the like.
Examples of ink formulating agents include antimicrobial and antiseptic agents, pH adjusters, chelating agents, antirusting agents, water-soluble UV absorbing agents, water-soluble polymeric compounds, dye solubilizing agents, surfactants and the like.
Examples of antimicrobial and antiseptic agents include anhydrous sodium acetate, sodium sorbate, sodium 2-pyridinethiol-1-oxide, sodium benzoate, sodium pentachlorophenol and the like.
As pH adjusters, any substances can be used as long as they can adjust pH of an ink within the suitable range, for example, in the range from 8.0 to 11.0 without adversely affecting the ink to be formulated. Examples thereof include alkanolamines such as diethanolamine and triethanolamine; alkali metal hydroxides such as lithium hydroxide, sodium hydroxide and potassium hydroxide; ammonium hydroxide; alkali metal carbonates such as lithium carbonate, sodium carbonate and potassium carbonate; and the like.
Examples of chelating agents include sodium ethylenediamine tetraacetate, sodium nitrilotriacetate, sodium hydroxyethylethylene diamine triacetate, sodium diethylenetriaminepentacetate, sodium uracil diacetate and the like.
Examples of antirusting agents include acidic sulfite, sodium thiosulfate, ammonium thioglycolate, diisopropylammonium nitrite, pentaerythritol tetranitrate, dicyclohexylammonium nitrite and the like.
Examples of water-soluble polymeric compounds include polyvinyl alcohol, cellulose derivatives, polyamine, polyimine and the like.
Examples of water-soluble UV absorbing agents include sulfonated benzophenone, sulfonated benzotriazole and the like.
Examples of dye solubilizing agents include xcex5-caprolactam, ethylene carbonate, urea and the like.
Examples of surfactants include any known surfactants of anionic, cationic and nonionic types.
The colored article of the present invention means any article colored with the compound of the present invention or the aqueous ink composition containing said compound. Examples of the articles to be colored include, but not to be limited to, papers, fibers and clothes (cellulose, nylon, wool and the like), leathers, substrates for color filter and the like. Any coloring methods which can be mentioned are the printing method such as the dip dyeing, the textile printing, or the screen printing and the method by means of ink jet printers. Among these coloring methods, printing with an ink jet printers is preferred.
Suitably, the aqueous ink composition containing the compound represented by the general formula (1) and optionally any other compound (dye) is useful for printing, copying, marking, writing, drawing, stamping and recording, particularly ink jet printing. Thereby, black prints of high quality having a remarkably full depth of shade and good resistances properties to water, light and abrasion can be obtained. The trisazo compound represented by the general formula (1) of the present invention exhibits improved color fastness to light, especially when applied onto papers intended for ink jet printing.
The aqueous ink composition of the present invention does not produce precipitates during its storage. In case the aqueous ink composition of the present invention is used in ink jet printing, it does not cause the clogging of a jet nozzle. And, when continuously used in the ink jet printer with certain recirculation for considerably long time or intermittedly used in the ink jet printer, the aqueous ink composition of the present invention shows no change in physical properties.